The present application is related to, and claims priority from, Japanese Patent Application No. Hei. 10-335947, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to bar code readers, and more particularly to a bar code reader whose thickness is reduced as a whole due to the location and size of its optical sensor configuration.
2. Description of the Related Art
A conventional bar code reader utilizes an optical reader for illuminating a bar code affixed to a product. The bar code reader light images the bar code from light reflected from the bar code via an optical imaging system, and then reads the bar code image via an optical sensor, such as a CCD array, disposed at a predetermined reading position within the reader.
In a conventional reader such as the one just described, the optical sensor is configured in a manner such as that shown in FIG. 6A. As shown, the optical sensor 36 is composed of a sensor body and a sensor substrate. A flat wire 37a is soldered to the sensor substrate at one end and to a mounting substrate 38 at the other end to affix the optical sensor 36 to the mounting substrate 38. The total component height h including the optical sensor 36 and the mounting substrate 38 is the distance from the lower end of the flat wire protruding from the mounting substrate 38 to the upper end of the sensor substrate.
Japanese Patent Application Laid-Open No. Hei. 7-210622 describes a bar code reader having alternate structures such as those shown in FIGS. 6B and 6C in which a lead terminal 37b (or terminals 37c, 37d) directly affixes the sensor body 36a to the mounting substrate 38 without a sensor substrate, thereby reducing the overall height h of the sensor configuration.
More specifically, the component height h in FIG. 6B is the sum of the height of the sensor body 36a, the length of the lead terminal 37b, and the thickness of the mounting substrate. The component height h in FIG. 6C is the sum of the height of the sensor body, the length from the lower end of the sensor body to the bottom edge of the lead terminal protruding through the mounting substrate, and the thickness of the mounting substrate.
Alternatively, if the sensor body is positioned in direct contact with the mounting substrate, the component height in such a case would be the height of the sensor body plus the thickness of the mounting substrate and the length of the lead terminal protruding the bottom side of the mounting substrate.
In any case, the height h of the parts including the optical sensor and the mounting substrate will always be at least the height of the optical sensor plus the thickness of the mounting substrate. Therefore, even if the height of the other circuits disposed on the mounting substrate is small, the height of the optical sensor determines the thickness of the apparatus at the mounting substrate location in the above sensor configurations.
Due to the ongoing demand for smaller and easier to handle readers, it is desirable to minimize the size of the entire bar code reader apparatus. One way to reduce the size is to reduce the size of the reader handle, which is where the optical sensor configuration is located, to thereby enhance reader portability and to enable the handle to be more easily grasped. However, it is inherently difficult to reduce the thickness of the above-discussed prior art bar code reader due to the space required to mount the optical sensor on the mounting substrate.
In view of the above prior art limitations, it is an object of the present invention to provide an optical reader having an optical sensor configuration that enables the size of the reader to be reduced by greatly reducing the height of the optical sensor and mounting substrate combination when compared to prior art optical sensor configurations.
Specifically, the present invention provides a reader for optically reading target indicia. The reader includes an optical imaging system for taking light reflected from an object to be read and creating an image of the object from the reflected light. An optical sensor detects the image created by the optical imaging system so that the image can be processed. A mounting substrate defines a sensor aperture therein in which the optical sensor being is mounted to minimize a height of the optical sensor above the substrate.
In the above embodiment, the optical sensor is mounted partially within the sensor aperture, the overall height of the optical sensor and mounting substrate configuration, and consequently the sensor space requirements, are reduced compared to prior art configurations by a factor of at least the portion inserted through the sensor aperture. When the optical sensor is mounted within the sensor aperture so that the bottom surface of the sensor is co-planar with the bottom surface of the substrate, the height of the optical sensor and mounting substrate configuration is reduced to the height of the optical sensor. Therefore, the configuration thickness is reduced by at least a factor of the mounting substrate compared to prior art configurations. Accordingly, the optical reader of the present invention enables the overall size of the bar code reader to be reduced.
According to another embodiment of the present invention, an optical reader includes a mounting substrate, and an optical imaging system mounted to the mounting substrate for receiving reflected light from an object to be read, and for forming an image of the object from the reflected light. An optical sensor is electrically connected to the mounting substrate and is in optical communication with the optical imaging system.
The optical sensor includes an image-receiving surface for detecting the image formed by the optical imaging system for image processing purposes. This image-receiving surface is parallel with, and opposed to, a bottom surface of the mounting substrate. A light transmitting aperture is defined in the mounting substrate so that the image is transmitted from the optical imaging system through the light transmitting aperture and is incident on the image-receiving surface.
As with the above-discussed first embodiment, the second embodiment, through its uniquely arranged image sensor configuration enables the overall size of the reader to be substantially reduced when compared to conventional bar code readers.
The specific nature of the invention, as well as other objects, uses and advantages thereof, will clearly appear from the following description and from the accompanying drawings.